Atomizer



Dec. 14, 1937. w. c. GRAHAM ATOMI ZER Filed March 15, 1957 W F111 .4.6/i

INVENTOR WAZREJJ C.G2AHAM, BY

ATTORNEY Patented Dec. 14, 1937 UNITED STATES PATENT QOFFICE aromzsn Warren "0. Graham, New r rkfn. Y. Application March 15, 1931, Serial No. 130,877

I 5 Claims. lici. 299-120) This invention relates to mechanical atomizers or sprays for liquids, for example, atomizers for burners using liquid or colloidal fuels. More specifically, the invention relates to atomizers of 5 the whirling spray type, in which the liquid issues from a tip, sprayer plate or nozzle with a spinning motion which causes the spray to assume the shape of a cone, preferably a hollow cone.

1 The object of the invention is to improve the atomizing qualities of such devices, so that a finer spray may be produced than hasheretofore been attainable or-a lesser feed-pressure may be employed to produce sprayso'f the degree of fine,-

.. l ness realized by the best'known atomizers.

In the accompanying drawing and description,

the invention has been illustrated as applied to. a preferred and well-known type .of liquid fuel atomizer in which the fuel is delivered to a series 20 of slots or conduits disposed transversely and tangentially to the axis of the atomizer and communicating with a central whirl chamber from which the atomizer orifice leads. While the invention in its broadest aspect, may take other 25 atomizer mentioned.

Broadly, the invention comprises means which imparts a whirling motion to a flowing stream' of liquid, delivers the whirling stream into an ex- ,m ,pansion chamber, wherein the heavier particles are separated fromthe lighter by centrifugal force, and conducts the separated particles to the orifice of a spray nozzle. More specifically the invention comprises a device in which the whirl- *5 Figure 4 is a developed or diagrammatic view 0? a larger scale, showing the relations of some 0 the liquid passages;

Inthe'drawing, l designates a supply pipe for"- liquid fuel or other liquid. This pipe is provided 50 with an externally threaded nipple.2 upon which is screwed body member 3 of a spray nozzle. The body member has a reduced externally threaded extension 4 upon which is screwed a gland nut 5. The gland nut has an inner flange 6 which 55 clamps a spray tip 1 against the end of body tip bears against plug 8 and-its forms, it is particularly adapted to the type of Q member 3. It will be noted that,- except for certain recesses and passages, hereinafter referred to, the outer end of body member 3 is closed by a plug or partition 8. The central part of spray periphery is seated upon a shoulder 9 formed on the body member.

Spray tip I is of usual construction. It has an orifice Ill communicating with a whirl chamber II and tangential slots H which lead into the 10 whirl chamber at its periphery. The outer and inner-faces of the spray tip are preferably fiat,

, as shown. The ratio of the total area'of the tangential slots to the size of the orifice is of great impgrtance and. this ratio may be varied to produce corresponding changes in the size, shape and other'characteristics of the resulting spray or flame.

Immediately behind the inner face of the spray tip, I provide an auxiliary whirl chamber I3,

which, inconiunction with means for supplying whirling liquid to the chamber, comprises the most essential feature of the invention. Chamber I3 is preferably of the annular form shown, being bounded outwardly by the wall of extension l and inwardly by plug 8. Any suitable means may be utilized for imparting a whirling motion to the' liquid before it enters the chamber l3. The means shown. is' one of several well-known devices for this purpose. It comprises a series again to form a homogeneous mixture, they are forced into the tangential slots, thence into whirl chamber 'II where they are broken down into still finer particles, and finally through the oriflee of the sprayer tip. Subdivision" of the particles is further aided by the rapid movement ofthe stream of liquid in whirl chamber It in a circular direction, i. e., across. the tangential slots. While some of the particles enter the. nearest slot and others sweep past to enter succeeding slots, still other particles impinge upon the trailing shoulders or corners of the'slots and are broken up by the shearing effect thus produced.

The spinning of the fuel in whirl chamber I3 and subsequent delivery to the tangential slots, should not be confused with the barrelling effect employed in some existing 011 burners for the mere purpose of rotating the fuel before it leaves been found that the maximum obtainable ato'mb zation is produced by a pressure of 300 lbs. With pressures below 300 lbs., atomization is inadequate and higher pressures do not noticeably increase the fineness of the spray. Tests have shown that the addition of my improvements to an otherwise standard sprayer tip makes it possible to produce the maximum atomization heretofore obtainable with a pressure of- 150 lbs. Moreover, when higher pressures up to 300 lbs. are used, the spray is finer than any heretofore known.

It will be observed that the diameter of the central solid portion of plug 8 determines how much of the tangential slots shall be open to whirl chamber l3, the remainder of the slots constituting ducts into whirl chamber II. By making this diameter larger or smaller, the length of travel in the slots is varied and corresponding changes in the characteristics of the spray result.

I claim:-

1. A spray nozzle comprising in combination, a sprayer tip having an orifice and tangential slots communicating therewith, a whirl chamber behind the sprayer tip and communicating with the slots, and means for delivering whirling liquid to said whirl chamber.

2. A spray nozzle comprising in combination, a sprayer tip having an orifice and a whirl chamber and tangential slots communicating with the whirl chamber, an annular auxiliary whirl chamber behind the sprayer tip and communieating with the slots, and means for delivering whirling liquid to the auxiliary chamber.

3. A spray nozzle comprising in combination, a sprayer tip having an orifice and a whirl chamber and tangential slots communicating with the whirl chamber, an annular auxiliary whirl chamber behind the sprayer tip and communicating with the slots through a portion of their lengths at their outer ends, and means for delivering whirling liquid to the auxiliary chamber.

4. A spray nozzle comprising in combination, a

sprayer tip having an orifice and a whirl chamher and tangential slots communicating with the whirl chamber, the slots being open rearwardly ,for only a portion of their lengths at whirl chamber.

5. A spray nozzle comprising in combination, a sprayer tip having an orifice and a whirl chamber and tangential slots communicating with the whirl chamber, the whirl chamber and slots being open rearwardiy, a hollow body member behind the sprayer tip, the body member having, first, an opening for the admission of liquid under pressure, and second, a front wall lying across the rear face of the sprayer tip, the front wall having an annular recess in its front face adjacent the outer ends of the tangential slots, and holes connecting the interior of the body member with the annular recess, the holes being inclined in a direction having a tangential component with respect to the annular recess.

' WARREN C. GRAHAM. 

